sport jet 120 water in bottom 2 cylinders

[stang7tl]

ok so I am not sure if is because of the exhaust gasket or if it will happen if you have the house running on the engine with it not running? will it back feed in or is the gasket probably it? I am going to buy new plugs and getting it running again and see if these plug get wet when running in the water but if any one can help
Thanks

 

[pnwboat]

Re: sport jet 120 water in bottom 2 cylinders

I would suspect either head gasket or exhaust cover gasket is bad. Possible crack in the exhaust plate. Even running on hose with motor off, you should not get water in the cylinders.

 

[moparman]

Re: sport jet 120 water in bottom 2 cylinders

the 120's had a problem with the exhaust plate splitting, and sometimes you had to really look close to find them. Also check the plate gasket closely. Hope this helps you , keep us posted with what you find. MOPARMAN

 

[stang7tl]

Re: sport jet 120 water in bottom 2 cylinders

can you explain how to check this? do I unbolt the exhaust manifold and etc.

 

[stang7tl]

Re: sport jet 120 water in bottom 2 cylinders

I would suspect either head gasket or exhaust cover gasket is bad. Possible crack in the exhaust plate. Even running on hose with motor off, you should not get water in the cylinders.

how do i find out which one? will a compression test tell me if it is the head gasket? and how to check the exhaust gasket?

 

[pnwboat]

Re: sport jet 120 water in bottom 2 cylinders

Compression test will tell you if the head gasket is bad. If compression test is OK, then I would take the exhaust cover off and check the gasket. You should be able to see any defective spots in the gasket, or cracks in the exhaust plate. Don't know of any other way to check the exhaust cover gasket and exhaust plate.

 

[stang7tl]

Re: sport jet 120 water in bottom 2 cylinders

so the compression test on cylinder 1 was around 150 and the other 3 are around 170-175. but only the bottom 2 cylinders seem to be getting water in them so I guess it is the exhaust manifold gasket? does that sound right?

 

[pnwboat]

Re: sport jet 120 water in bottom 2 cylinders

I would say so....

I just realized that you have a Sport Jet. It has the large manifold with the big exhaust tube that hangs off of it??? if so then there is no exhaust plate under the exhaust cover. It also take a special exhaust cover gasket. Make sure you get one specifically for a Sport Jet.

 

[moparman]

Re: sport jet 120 water in bottom 2 cylinders

Either the gasket or plate is leaking.I've had a plate on a 120 that you had to flex once it was off to find the crack. With this being an L drive it might not even have the same type of exhaust plate as whats on a regular 120, but you'll have to look to find out,I'm not sure of it as I've never been in the exhaust of the L drive motor.Just look very closely at it and keep us posted as to what you find. Hope this helps , MOPARMAN

 

[moparman]

Re: sport jet 120 water in bottom 2 cylinders

I just looked up the sportjet and it does not have the plate like i mentioned earlier. unless the thick manifold is cracked, its going to be the gasket as pwboat mentioned.Just trying to get the info right ,sorry about that,but as I said I've never worked on the exhaust of an L drive. Keep us posted on your progress MOPARMAN

 

[x1745]

Re: sport jet 120 water in bottom 2 cylinders

Did you tested it in the water or you used the flush adapter?
Remove all spark plugs and spray 1 tea spoon of fog oil in each cylinder and crank the engine until no more water in those two bottom cylinders
It happened to me when I use the flush adapter with too much water pressure
That caused water get in two bottom cylinders
Hope that help

 

[stang7tl]

Re: sport jet 120 water in bottom 2 cylinders

in the water boat was running ok not its best sound like it was missing but then it was running great at some pulls. we beach the boat and then was going to leave and it wouldn't start pulled the plugs and they looked like water and gas on them. As i tried to start it it began not to want to turn over like the cylinder had to much pressure I am guessing from turning it over the water licked into the cylinder? But I have the exhaust manifold off after breaking 6 of the 25 bolts LOL they used to small of bolts plus the age and etc. So I will be re threading the bolts holes and putting it back together hoping the new gasket solve it

 

[pnwboat]

Re: sport jet 120 water in bottom 2 cylinders

You can put some anti-seize compound on the bolts to help prevent them from breaking off in the future.

 

[r_bremmer]

Re: sport jet 120 water in bottom 2 cylinders

so once you get water in the cyl. after too much pressure on a dealer flush kit, you have to replace the exhaust gasket, or is it possible it can run without a replaced gasket after things are dried out?

 

[stang7tl]

Re: sport jet 120 water in bottom 2 cylinders

NOW here is another question
the water is out and new gasket in, but the motor has a tuff sport when cranking. we hope it is just some build up of rust and we can work it out. but I am also thinking it might be a bent rod?
So how can I tell?
It did fire for me but shut off

 

[pnwboat]

Re: sport jet 120 water in bottom 2 cylinders

You may have had some rust form on the cylinder walls from the water leak. If so, soak the cylinders with some WD-40 or similar product to break the rust free, and turn the motor over slowly by hand in the same direction it normally runs to distribute the WD-40 evenly. Let it soak for a while and try cranking it with the spark plugs out. Make sure you don't have the kill switch in the normal running position. This will prevent the ignition system from firing and possibly damaging the CD modules. Re-install the plugs, put the kill switch in the normal running position and fire it up.

 

[ThrashN]

Re: sport jet 120 water in bottom 2 cylinders

I have a 95 sea rayder with a 120 also. I had the same thing happen to me. Water in the bottom 2 cylinders. Looks like it was a blown gasket. I have motor out right now doing a rebuild

 

[stang7tl]

Re: sport jet 120 water in bottom 2 cylinders

motor still has a sticking spot any other ideas ?